Messier 109

Discovered by Pierre Méchain on March 12, 1781.
Independently rediscovered by William Herschel on April 12, 1789.

Messier: M109.

(from the description of M97) A Nebula which is near Gamma UMa.

(Messier added a position by hand which was identified by Owen Gingerich in 1953 as that of H IV.61 = NGC 3992, which is now called M109)

(manuscript:) Nebula near Gamma UMa, same right ascension a bit near this star and 1 deg .. more south. Discovered by M. Méchain on March 12, 1781.

Méchain

(in his letter to Bernoulli, May 6, 1783)
Page 265 No. 97 [M97]. A nebula near Beta in the Great Bear. Mr. Messier mentions, when indicating its position, two others, which I also have discovered and of which one is close to this one [M108], the other is situated close to Gamma in the Great Bear [this is M109], but I could not yet determine their positions.

William Herschel: H IV.61.

IV.61. Apr. 12, 1789.
cB. BrN with vFE branches about 30deg np sf. 7 or 8' l, 4 or 5' b.
Considerably bright. Bright resolvable [mottled, not resolved] nucleus with very faint extended branches to position angle 30deg north preceding to south following. 7 or 8' long, 4 or 5' broad.

John Herschel (1833): h 1030.

h 1030 = H IV.61.
Sweep 328 (February 17, 1831)
RA 11h 48m 41.3s, NPD 35d 40' 33" (1830.0). [Right Ascension and North Polar Distance]
vB; vL; R; smbM; 3' diam.
Very bright; very large; round; suddenly much brighter toward the middle; 3' diameter.

John Herschel, General Catalogue: GC 2635.

GC 2635 = h 1030 = H IV.61.
RA 11h 50m 15.6s, NPD 35d 50' 34.2" (1860.0). [Right Ascension and North Polar Distance]
cB; vL; pmE; sbMBrN. 3 observations by W. & J. Herschel.
Considerably bright; very large; pretty much extended; suddenly brighter to the middle where there is a bright mottled nucleus.

Dreyer: NGC 3992.

NGC 3992 = GC 2635 = h 1030 = H IV.61.
RA 11h 50m 19s, NPD 35d 51.3' (1860.0). [Right Ascension and North Polar Distance]
cB, vL, pmE, sbMBrN; = M109
Considerably bright, very large, pretty much extended, suddenly brighter to the middle where there is a bright mottled nucleus.

Curtis

[Descriptions of 762 Nebulae ans Clusters photographed with the Crossley Reflector. Publ. Lick Obs., No. 13, Part I, p. 9-42]
NGC 3392, RA=11:52.4, Dec=+53:55. A beautiful, slightly oval spiral 7' in length. Bright, almost stellar nucleus; whorls are rather open and show a number of faint condensations; the central portions show signs of Phi-type formation [the bar]. 20 s.n.